[1] Univ Chile, Fac Dent, Evidence Based Dent Unit, Santiago, Chile
[2] McMaster Univ, Dept Clin Epidemiol & Biostat, Hamilton, ON, Canada
[3] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[4] Univ Toronto, Fac Dent, Dent Publ Hlth, Toronto, ON, Canada
[5] Univ Toronto, Fac Med, Inst Hlth Policy Management & Evaluat, Clin Epidemiol & Hlth Care Res, Toronto, ON, Canada
[6] Mt Sinai Hosp, Endodont, Toronto, ON M5G 1X5, Canada
[7] SUNY Buffalo, Sch Dent Med, Buffalo, NY 14260 USA